Lawrie has already provided a substantial answer, but here's a bit more. On Wednesday 03 January 2007 19:31, David Anderson wrote: > Hey all, > > I was wondering how far the effort to port Lejos to the nxt has gone. > > If you remember that, I'm the guy who wrote libnxt, and who wants to > get his own firmware booted on the nxt (http://nxt.natulte.net/). I've > been out of the world for a while (work work work), but now I'm back, > with a new NXT kit, and I've started making some nice progress on > getting something booted properly.
If you've been around ARM-based micros before, then getting going on the low-levels is not too difficult. The hardest part was getting the i2c link to the AVR going properly because the documentation did not match what was happening, compunded by the fact that the SAM7 I2C peripheral is buggy. As Lawrie has already stated, we can run code in three ways, one of which supports gdb-level debugging through jtag. > > In the interest of not duplicating efforts, I'd like my code and Lejos > to at least share a common base. I don't have much interest in running > a Java VM on the nxt myself, but the low-level kernel code should be > flexible enough to accomodate that. My current plan is to have the > kernel boot a single "userspace" program once it's finished > initializing the hardware. That program could, in lejos' case, be a > java VM that does more initialization and executes java bytecodes. That's the model being used here. Just replace main with the code you want and you're off to the races. Since I've used dead code stripping, you can even leave the VM code in the build (but don't call it :-)) and it will just get stripped from the final image. At this stage, the code is structured to have all housekeeping done in interrupt land. There is a "poor man's" supervisor thread (supervisong AVR comms etc) which is just a low priority interrupt. > > Has Lejos started developing its nxt firmware using Lego's source > code, or their own code, or... What? :-) We got a substantial distance down the road before the Lego fw was available. Thus far I've only used it to confirm a few things I've seen on a scope etc. In the longer term I think having an independent codebase is quite useful. -- CHarles ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Lejos-discussion mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/lejos-discussion
